Ore concentrator



A. LE ROY BURKETT ETAL 3,065,919

Nov. 27, 1962 ORE CONCENTRATOR 3 Sheets-Sheet 2 Filed Sept. 6, 1960INVENTORS NOW 1962 A. LE ROY BURKETT ETAL 3,065,919

ORE CONCENTRATOR Filed Sept. 6. 1960 3 Sheets-Sheet 3 INVENTORSfliimrliiarhP/rzrr 5/005 7: E T

' v %EY United States Patent ice 3,065,919 ORE CONCENTRATOR Albert LeRoy Burkett, and Andrew T. Sweet, Denver, Colo., assignors, by directand mesne assignments, to Colorado Manufacturing & Mining (30., Inn,Denver, Colo., a corporation of Colorado Filed Sept. 6, 1%8, Ser. No.53,958 3 Claims. (ill. 241-161) This invention relates to a machine forcomminuting consolidated sedimentary rocks andrecovering the mineralvalues therefrom.

Natural sedimentary rocks comprise sand grains cemented or attachedtogether by various alluvial materials toform solid rock masses. Incertain localities, it has been found that mineral values such asuranium, copper, zinc, molybdenum, etc., have been entrapped between ordeposited upon the individual sand grains. Heretofore, it has beencustomary to crush these con glomerate masses or pieces -tosubstantially grain size and to then subject the grains to a finalgrinding or powdering step to liberate the mineral values so that ahydraulic separation could be made between the intersticial,mineral-carrying coating material and the pulverized sand grains. Thisfinal fine grinding produces a large volume of valueless sludge materialand so increases the milling costs that it is profitable to mill onlythe exceedingly high grade ores having a high percentage of mineralvalues although vast amounts of mineral values are present in the oresof lower grade.

The principal object of this invention is to provide a method and meanswhich will make the expensive fine grinding of the rock grainscompletely unnecessary and which will reduce the conglomerate materialto grain size without crushing the grains and which will recover thevalue-carrying intersticial cementing material from the grains so as toproportionately reduce milling cost to enable the lower grade ores to beworked and to enable a higher profit to be made from the higher gradeores.

Another object is to provide means for scouring the grains to remove allvalue-carrying material from the surfaces thereof and thence separatingthe material re- .moved from the grains from the grains themselvesthereby eliminating the m'ost costly of all milling operations, that is,the exceedingly fine grinding.

A further object of the invention is to provide a dry i oreconcentrating device which will disintegrate the consolidated sedimentsto grain size and simultaneously .abrade and polish the surfaces of thegrains to remove the intersticial cementing material in which the valuesare contained, in the form of a dust which can be collected in anysuitable recovery device to produce a valuable dry concentrate of themineral values.

A still further object of the invention is to provide,

, in a machine designed to break down consolidated sediments and abracleand scour the resulting grains, means tion.

In the drawings: FIG. 1 is a side elevational View of the improved orecomminuting and concentrating machine partially broken away to show theinterior elements;

FIGS. 2 and 3 are horizontal cross sectional views lookdownwardly on thelines 22 and 3--3, respectively,

FIG. 4 is a detail fragmentary enlarged section of a portion of thesectional area of FIG. 1 illustrating the type of sand pockets asemployed in the machine; and

FIG. 5 is a vertical medial cross section taken on the line 55, FIG. 2.

Briefly, the machine comprises a plurality of rapidly rotating,superimposed, axially-aligned, relatively fiat, annular discs whichreceive the conglomerate rock particles and throw them centrifugally andtangentially outward against an enclosing wall with an impact sufiicientto comminute the particles into grains and to abrade, scour and polishthe surfaces of the resulting grains to produce a valuable dustconcentrate which is constantly and permanently removed.

As illustrated, the machine comprises a vertical shaft 10 rotatablysupported in a lower thrust bearing 11 and an upper guide bearing 12.The lower thrust bearing 11 is supported upon radial beams 13 extendingto and supported by four vertical supporting columns 14. The upper guidebearing 12 is maintained in vertical alignment with the bearing 11 bymeans of radial supporting arms 15 extending from and supported by thecolumns 14. The shaft 10 is rotated through the medium of thetransmission belts 16 extending from a drive sheave 17 on a shaft drivemotor 18, mounted on one of the columns 14, to a driven sheave 19mounted on the shaft 10 adjacent its lower extremity.

A feed distributing disc 20 is mounted on the shaft 10 above the guidebearing 12 and a plurality of annular throwing discs 21 are mounted onthe shaft 10 in vertically spaced relation between the bearings 11 and12. Each throwing disc 21 is supported on a plurality of radial spokes22 extending from a hub 23 fixed upon the shaft 10. The annular shape ofthe discs outlines a circular axial air passage 24 through each discwhich is surrounded by an annular upstanding guard flange 25.

The throwing discs are enclosed in a vertical cylindrical barrel 26which is supported by means of lower spokes 27 and a lower hub 23 from athrust bearing 28 so as to be rotatable about but axially immovable onthe shaft 10. The upper extremity of the barrel 26 is maintained inconcentric relation with the shaft by an upper guide bearing 29 fromwhich radial spokes 30 extend to the periphery of the barrel. Thus, itcan be seen that the barrel 26 may rotate independently of the shaft 19.

The barrel contains a plurality of cast liner rings 31 superimposed uponeach other in stacked relation, therebeing one liner ring substantiallyin the plane of each throwing disc 21. Each liner ring is provided withan internal annular sand pocket 32. An annular, conicallyinclined funnelplate 33 extends inwardly and downwardly from the sand pocket 32 in eachof the liner rings 31 to a position over the axial portion of the nextlowermost throwing disc 21, as shown in FIG. 1.

The barrel 26 is rotated independently of the shaft 10 in any desiredmanner. As illustrated, it is rotated through the medium of a frictiondrive wheel 34, preferably rubber-tired, mounted on one of the columns14 in contact with the exterior of the drum and driven from a seconddrive motor 35 through the medium of a second transmission belt drive36. Additional-lateral support for the barrel is provided by means ofidler wheels 37 mounted on vertical shafts 38 in bearings 39 on thecolumns 14.

An annular feed ring 40 having an inwardly and down Patented Nov. 27 1962 apes.

wardly depending annular apron 41 is supported over the barrel 26 in anydesired manner, such as by being fixedly mounted upon the arms 15 of theupper guide bearing 12, as indicated at 42. The feed hopper 40 ispreferably closed by means of a cap plate 43 through which aconcentrically-positioned ore feed chute 44 enters. An annular conicalbottom plate 45 is positioned in the bottom of the barrel 26. The bottomplate 45 has a central, flanged, air passage 46 and is preferablysupported on the lower spokes 27 so as to direct material toward anannular discharge passage 47 about the periphery of the lower extremityof the barrel 26.

An annular ore receiving trough 48 is supported below the barrel 26 inany suitable manner such as by means of cross braces 49 extending to thecolumns 14. The top of the annular trough 48 is open so as to receivematerial falling through the annular discharge passage 47 from thebarrel. The bottom of the receiving trough 48 is contoured to form aplurality of hoppers 50, each of which directs material into a verticaldischarge conduit 51. The discharge conduits 51 discharge through a topplate 52 on a collection chamber 53 supported from the columns 14 bymeans of suitable bracing 54. The chamber 53 directs material to atailings discharge collar 55 through which the tailings are dischargedfrom the machine.

A circular, cup-shaped, open-topped air suction chamber 56 is positionedwithin the confines of the annular trough 48, from which an air suctionconduit 57 leads to the intake of any suitable conventional suction fanor blower by means of which air is constantly drawn downwardly throughthe feed chute 44, the feed ring 40, the air passages 24 in the discs21, and the discharge passage 47 in the bottom plate 45. It isconceivable that blower blades could be mounted on the shaft within thecircular chamber 56 to draw air downwardly about the shaft 10 anddischarge it through the conduit 57 if desired.

The motors, the sheaves and the belt transmission devices are soproportioned that the shaft 10 is rotated at from 500 to 800 rpm. whilethe barrel 26 is rotated at from 38 to 50 r.p.m. They may be bothrotated in the same direction. It is preferred, however, to rotate thebarrel in a direction opposite to that of the shaft.

Let us assume that crushed conglomerate, mineral bearing ore is beingfed into the feed chute 44 onto the feed disc 20. The rotation of thelatter disc will throw the ore particles forcibly against the innersurface of the feed ring 40 with a resulting fractionation of theparticles. The fractioned particles will then be directed inwardly anddownwardly by the annular ring apron 41, against the guard flange 25 ofthe uppermost throwing disc 21.

The rapid rotation of the latter throwing disc will instantly impartcentrifugal force to the particles so as to throw them tangentiallyoutward with great force into the sand pocket 32 of the uppermost linerring 31 resulting in additional fractionation. The further fractionatedparticles will now roll inward down the incline of the uppermost funnelplate 33 to the inner periphery of the second throwing plate where athird fractionation will take place as above described.

The particles continue to cascade downwardly from throwing plate tothrowing plate at each of which the above fractionation will berepeated. The particles will finally fall from the sand pocket of thelowermost liner ring and will be guided by the conical bottom plate 45into the trough 48 and from thence through the conduits 51, thecollection chamber 53 to the tailings discharge 55.

The successive impacts against the liner rings and the constant andviolent rolling and throwing will scour the rock grains of the adhering,value-containing, cementitious material and create a dust thereof. Thisvaluable dust will be constantly removed by the downwardly flowing airstream and the dust laden air will be treated in conventional cyclones,filters, etc., for the removal of the solid concentrate. The rock grainswill be discarded at the tailings discharge.

The liner rings are subjected to a continuous and violent sand blastwhich would normally rapidly wear the rings away. However, in thisdevice, each of the metallic rings is constantly protected by an annularsand cushion as indicated at 58 in FIG. 4. These annular sand cushionsare maintained in place in the sand pockets 32 by the centrifugal forcecreated by the rotating barrel. The sand forming the cushions isconstantly changing due to the continuous impact of the incoming sandbut always a sufficient amount is present to reduce abrasion.

The machine has an exceedingly large capacity, for instance, withthrowing plates 5'0" in diameter rotating at 600 rpm. with a peripheralspeed of 9400 f.p.m. the machine will efliciently treat and concentratefrom 5 to 6 tons of ore per minute.

While a specific form of the improvement has been described andillustrated herein, it is to be understood that the same may be variedwithin the scope of the appended claims, without departing from thespirit of the invention.

Having thus described the invention what is claimed and desired securedby Letters Patent is:

1. An ore concentrator comprising: a rotatable, vertical shaft; meansfor rotating said shaft; a vertical, cylindrical barrel enclosureconcentrically surrounding and radially spaced from said shaft andjournalled thereon; a plurality of annular throwing discs mounted onsaid shaft in vertically-spaced relation, said discs having mediallypositioned openings; means for feeding ore onto the uppermost disc to bethrown tangentially outward against the interior of said barrelenclosure; a feed distributing disc mounted on said shaft overlying andspaced axially from the uppermost throwing disc, said distributing disccovering the openings in the uppermost throwing disc and preventingentrance of ore therein; annular funnel plates supported from saidenclosure intermediate said discs for successively returning materialfrom said barrel enclosure to the next lowermost disc; an annularconical bottom plate mounted on said shaft below the lowermost disc anddirecting material falling from the latter disc radially outward to acircumferential discharge; an annular receiving trough positioned belowsaid circumferential discharge; discharge conduits discharging materialfrom said trough; a circular air chamber positioned below said conicalbottom plate and within the confines of said annular receiving trough,said air chamber opening upwardly through the medial openings in saiddiscs; and means for drawing air from said air chamber.

2. An ore concentrator as defined in claim 1 and having means to mountsaid barrel enclosure freely on said shaft, and means to rotate saidenclosure in a direction opposite to said shaft.

3. An ore concentrator comprising: a rotatable vertical shaft; means forrotating said shaft; a plurality of circular, throwing discs mounted onsaid shaft in vertically-spaced relation said discs having air passagesadjacent the axes; a feed distributing disc mounted on said shaftoverlying and spaced axially from the uppermost throwing disc, saiddistributing disc covering the openings in the uppermost throwing discand preventing entrance of ore therein; a vertical cylindrical barrelconcentrically surrounding said shaft and rotatably mounted thereon; aplurality of super-imposed annular liner rings fitted into said barrel,there being one liner ring for each disc; means for feeding ore ontosaid discs to be thrown tangentially outward against their respectiveliner rings; upper and lower spoked members in said barrel, said spokedmembers being mounted on said shaft so as to be rotatable relativethereto; a thrust bearing means supporting said spoked members on saidshaft and main- 5 6 taining the liner rings in the planes of theirrespective the openings in said discs; means for drawing air from discs;a conical bottom plate in the bottom of said said suction chamber; andmeans for rotating said barrel barrel and directing ore outwardly tocircumferential independently of said shaft.

discharge, said bottom plate having an air passage its axiscommunicating with the air passages in said discs; 5 References Citedill the file of this P an annular stationary receiving trough positionedbelow UNITED STATES PATENTS said circumferential discharge and a suctionchamber positioned within the confines of said trough below and 2 5 322223 igg in close relation to said bottom plate to draw an down- 981,489Hannum p 25, W61

wardly through the openings in said bottom plate and 10

